U.S. patent application number 10/803380 was filed with the patent office on 2004-12-16 for plasma display panel apparatus and driving method thereof.
Invention is credited to Yoo, Sung-Hune.
Application Number | 20040251847 10/803380 |
Document ID | / |
Family ID | 33509566 |
Filed Date | 2004-12-16 |
United States Patent
Application |
20040251847 |
Kind Code |
A1 |
Yoo, Sung-Hune |
December 16, 2004 |
Plasma display panel apparatus and driving method thereof
Abstract
In a PDP apparatus a first protrusion is formed in the column
direction at a scan electrode. A second protrusion is formed in the
column direction at a sustain electrode. The first and second
protrusions face each other with a protrusion gap therebetween. An
area of the first protrusion is greater than that of the second
protrusion. A first sustain pulse is applied to the scan electrode
and a second sustain pulse is applied to the sustain electrode in a
sustain interval. In an exemplary embodiment a first interval
during which a voltage of the first sustain pulse is less than that
of the second sustain pulse is longer than a second interval during
which a voltage of the first sustain pulse is greater than that of
the second sustain pulse.
Inventors: |
Yoo, Sung-Hune; (Ahsan-si,
KR) |
Correspondence
Address: |
CHRISTIE, PARKER & HALE, LLP
PO BOX 7068
PASADENA
CA
91109-7068
US
|
Family ID: |
33509566 |
Appl. No.: |
10/803380 |
Filed: |
March 18, 2004 |
Current U.S.
Class: |
315/169.4 |
Current CPC
Class: |
H01J 11/12 20130101;
H01J 2211/245 20130101; H01J 11/24 20130101 |
Class at
Publication: |
315/169.4 |
International
Class: |
G09G 003/10 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 18, 2003 |
KR |
2003-0016855 |
Claims
What is claimed is:
1. A plasma display panel apparatus comprising: a first substrate;
a plurality of first electrodes provided in a row direction on the
first substrate; and a plurality of second electrodes provided in
the row direction on the first substrate, formed between two
adjacent first electrodes, wherein: the first electrode and the
second electrode face each other with a predetermined electrode gap
therebetween; a sustain discharge is generated by a voltage
potential difference between the first electrode and the second
electrode; and an area of the first electrode is larger than that
of the second electrode.
2. The plasma display apparatus of claim 1, wherein: the first
electrode has a first protrusion formed in a column direction; the
second electrode has a second protrusion formed in the column
direction; the first protrusion and the second protrusion face each
other with the predetermined protrusion gap therebetween; and an
area of the first protrusion is larger than that of the second
protrusion.
3. The plasma display apparatus of claim 2, wherein a
column-directional length of the first protrusion is longer than a
column-directional length of the second protrusion.
4. The plasma display apparatus of claim 2, wherein a
row-directional width of the first protrusion is longer than a
row-directional width of the second protrusion.
5. The plasma display apparatus of claim 1, further comprising: a
second substrate facing the first substrate with a substrate gap
therebetween; and a plurality of third electrodes provided in the
column direction on the second substrate, wherein an address
discharge is generated by a potential difference between the third
electrode and the first electrode.
6. The plasma display apparatus of claim 1, wherein: a first
sustain pulse is applied to the first electrode and a second
sustain pulse is applied to the second electrode in the sustain
interval; a voltage of the first sustain pulse is less than a
voltage of the second sustain pulse in a first interval; a voltage
of the first sustain pulse is greater than a voltage of the second
sustain pulse in a first interval; and a voltage of the second
sustain pulse in the second interval is less than a voltage
obtained by subtracting a minimum voltage for generating a sustain
from the voltage of the first sustain pulse.
7. The plasma display apparatus of claim 1, wherein: a first
sustain pulse is applied to the first electrode and a second
sustain pulse is applied to the second electrode in the sustain
interval; and a first interval during which a voltage of the first
sustain pulse is less than a voltage of the second sustain pulse is
longer than a second interval during which a voltage of the first
sustain pulse is greater than a voltage of the second sustain
pulse.
8. The plasma display apparatus of claim 7, wherein a voltage of
the second sustain pulse in the second interval is less than a
voltage obtained by subtracting a minimum voltage for generating a
sustain from the voltage of the first sustain pulse.
9. A method for driving a plasma display panel apparatus having a
first electrode and a second electrode formed in parallel on a
first substrate, and an address electrode crossing the first
electrode and the second electrode and being formed on a second
substrate, the plasma display apparatus generating an address
according to a voltage potential difference between the first
electrode and the address electrode, comprising: in a sustain
interval, applying a first sustain pulse with a first voltage to
the first electrode, and applying a second sustain pulse with a
second voltage less than the first voltage to the second electrode
to generate a sustain; and applying a first sustain pulse with a
third voltage to the first electrode, and applying a second sustain
pulse with a fourth voltage greater than the third voltage to the
second electrode to generate a sustain, wherein: the first
electrode and the second electrode face each other with a
predetermined electrode gap therebetween; and the frst electrode
has an area greater than that of the second electrode.
10. The method of claim 9, wherein the second voltage is less than
a voltage obtained by subtracting a minimum voltage for generating
a sustain from the first voltage.
11. The method of claim 9, wherein an interval during which the
first sustain pulse has the third voltage is longer than an
interval during which the first sustain pulse has the first
voltage.
12. The method of claim 11, wherein the second voltage is less than
a voltage obtained by subtracting a minimum voltage for generating
a sustain from the first voltage.
13. The method of claim 9, wherein: the first electrode and the
second electrode respectively have protrusions; and the protrusion
of the first electrode has an area greater than that of the
protrusion of the second electrode.
14. The method of claim 13, wherein the length of the protrusion of
the first electrode is longer than the length of the protrusion of
the second electrode.
15. The method of claim 13, wherein the width of the protrusion of
the first electrode is greater than the width of the protrusion of
the second electrode.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to and the benefit of Korea
Patent Application No. 2003-16855 filed on Mar. 18, 2003 in the
Korean Intellectual Property Office, the entire content of which is
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] (a) Field of the Invention
[0003] The present invention relates to a plasma display panel
(PDP) apparatus and a driving method thereof.
[0004] (b) Description of the Related Art
[0005] The PDP is a flat panel display that uses plasma generated
by gas discharge to display characters or images and includes,
according to its size, more than several scores to millions of
pixels arranged in a matrix pattern.
[0006] Scan electrodes and sustain electrodes are formed in
parallel on one side of the PDP, and address electrodes crossing
them are formed on another side thereof. The sustain electrodes are
formed corresponding to the respective scan electrodes, and ends of
the sustain electrodes are coupled in common.
[0007] The method for driving the AC PDP includes a reset period,
an addressing period, a sustain period, and an erase period, in
temporal sequence.
[0008] The reset period is for initiating the status of each cell
so as to facilitate the addressing operation. The addressing period
is for selecting turn-on/off cells and applying an address voltage
to the turn-on cells (i.e., addressed cells) to accumulate wall
charges. The sustain period is for applying sustain pulses and
causing a sustain for displaying an image on the addressed cells.
The erase period is for reducing the wall charges of the cells to
terminate the sustain.
[0009] A general PDP pixel has red (R), green (G), and blue (B)
discharge cells. An address electrode is provided in a single
discharge cell, and protrusions of the scan electrode and the
sustain electrode face each other with a predetermined protrusion
gap therebetween. A discharge cell is selected by an address pulse
applied to an address electrode and a scan pulse applied to a scan
pulse in an address interval. A discharge cell selected in the
address interval is discharged by sustain pulses respectively
applied to a scan electrode and a sustain electrode in a sustain
interval.
[0010] Regarding a discharge phenomenon in the sustain interval,
light emission at cathodes of scan and sustain electrodes is
greater that at anodes thereof as shown in FIG. 1. Since the size
of the cathode that manifests 2/3 of the total emission is the same
as that of the anode in the prior art, an area for diffusing a
discharge at a cathode is reduced, and the luminance is accordingly
lost.
SUMMARY OF THE INVENTION
[0011] In one exemplary embodiment of the present invention, there
is provided a PDP apparatus for diffusing a discharge of a cathode
that substantially manifests 2/3 of the total light emission.
[0012] In an exemplary embodiment of the present invention is
provided a PDP apparatus which includes a first substrate. A
plurality of first electrodes is provided in the row direction on
the first substrate. A plurality of second electrodes is provided
in the row direction on the first substrate, formed between two
adjacent first electrodes. The first electrode and the second
electrode face each other with a predetermined electrode gap
therebetween. A sustain discharge is generated by a potential
difference between the first electrode and the second electrode. An
area of the first electrode is larger than that of the second
electrode.
[0013] In another exemplary embodiment, the first electrode has a
first protrusion formed in the column direction. The second
electrode has a second protrusion formed in the column direction.
The first protrusion and the second protrusion face each other with
the predetermined protrusion gap therebetween. An area of the first
protrusion is larger than that of the second protrusion.
[0014] In yet another exemplary embodiment, a column-directional
length of the first protrusion is longer than a column-directional
length of the second protrusion.
[0015] In still another exemplary embodiment, a row-directional
width of the first protrusion is greater than a row-directional
width of the second protrusion.
[0016] In a further exemplary embodiment, the PDP further includes
a second substrate facing the first substrate with a substrate gap
therebetween. A plurality of third electrodes is provided in the
column direction on the second substrate, wherein an address
discharge is generated by a potential difference between the third
and first electrodes.
[0017] In a yet further exemplary embodiment, a first sustain pulse
is applied to the first electrode and a second sustain pulse is
applied to the second electrode in the sustain interval. A voltage
of the first sustain pulse is less than a voltage of the second
sustain pulse in a first interval. A voltage of the first sustain
pulse is greater than a voltage of the second sustain pulse in a
first interval. A voltage of the second sustain pulse in the second
interval is less than a voltage obtained by subtracting a minimum
voltage for generating a sustain from the voltage of the first
sustain pulse.
[0018] In another exemplary embodiment of the present invention is
provided a method for driving a PDP apparatus. A first electrode
and a second electrode are formed in parallel on a first substrate.
An address electrode crossing the first and second electrodes is
formed on a second substrate. The PDP apparatus generates an
address according to a potential difference between the first
electrode and the address electrode. The method includes, in a
sustain interval, applying a first sustain pulse with a first
voltage to the first electrode. A second sustain pulse is applied
with a second voltage less than the first voltage to the second
electrode to generate a sustain. A first sustain pulse is applied
with a third voltage to the first electrode. A second sustain pulse
is applied with a fourth voltage greater than the third voltage to
the second electrode to generate a sustain, wherein the first and
second electrodes face each other with a predetermined electrode
gap therebetween. The first electrode has an area greater than that
of the second electrode.
[0019] In yet another exemplary embodiment, the second voltage is
less than a voltage obtained by subtracting a minimum voltage for
generating a sustain from the first voltage.
[0020] In still another exemplary embodiment, an interval during
which the first sustain pulse has the third voltage is longer than
an interval during which the first sustain pulse has the first
voltage.
[0021] In a further exemplary embodiment, the first and second
electrodes respectively have protrusions, and the protrusion of the
first electrode has an area wider than that of the protrusion of
the second electrode.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 shows a discharge phenomenon at scan and sustain
electrodes of a PDP.
[0023] FIG. 2 shows a simplified perspective view of a PDP
apparatus according to an exemplary embodiment of the present
invention.
[0024] FIG. 3 shows a configuration of an electrode of a PDP
according to an exemplary embodiment of the present invention.
[0025] FIGS. 4 through 7 show PDP drive waveforms according to
first through fourth exemplary embodiments of the present
invention.
DETAILED DESCRIPTION
[0026] As shown in FIGS. 2 and 3, the PDP includes two substrates 1
and 2 facing each other with a predetermined substrate gap 100
therebetween. A plurality of scan electrodes (Y electrodes) 10 and
a plurality of sustain electrodes (X electrodes) 20 are alternately
provided in the row direction on substrate 1. Protrusions 11 (11a
and 11b) are respectively formed on the top and the bottom of scan
electrode 10, and protrusions 21 (21a and 21b) are respectively
formed on the top and the bottom of sustain electrode 20.
Protrusions 11 and 21 of scan and sustain electrodes 10 and 20
operate for a discharge. Top protrusion 11a of scan electrode 10
and bottom protrusion 21b of sustain electrode 20 face each other
with a predetermined protrusion gap 51 therebetween, and bottom
protrusion 11b of scan electrode 10 and top protrusion 21a of
sustain electrode 20 face each other with a predetermined
protrusion gap 52 therebetween. Protrusions 11 and 21 are made of a
transparent dielectric material including ITO (indium tin oxide).
Transparent dielectric layer 30 and protection layer 40 are formed
on scan and sustain electrodes 10 and 20 and protrusions 11 and 21
to cover substrate 1.
[0027] A plurality of address electrodes 110 covered with
dielectric layer 120 is formed in the column direction on substrate
2. A space determined by address electrode 110 and adjacent scan
and sustain electrodes 10 and 20 forms a discharge cell. Address
electrodes 110 formed at protrusions 11 and 21 of scan electrodes
10 and 20 can have a wide width for easy discharge.
[0028] A barrier rib (not illustrated) can be formed on dielectric
layer 120 to partition the discharge cell, which is referred to as
a closed structure. Further, the barrier rib may not be formed, or
part of the barrier rib in the closed structure can be removed.
[0029] Referring to FIGS. 2 and 3, top and bottom protrusions 11a
and 11b of scan electrode 10 are alternately formed, and top and
bottom protrusions 21a and 21b of sustain electrode 20 are
alternately formed. R, G, and B phosphors are applied to three
discharge cells that are adjacent in a triangular format, and R, G,
and B discharge cells 140R, 140G, and 140B form single pixel 140,
which is referred to as a delta structure. In addition, top
protrusions 11a and 21a and bottom protrusions 11b and 21b can be
provided in the column direction and in parallel. R, G, and B
phosphors are applied to three discharge cells that are adjacent in
the row direction, and the R, G, and B discharge cells form a
single pixel, which is referred to as a stripe structure.
[0030] As shown in FIGS. 2 and 3, a column-directional length of
protrusion 11 formed at scan electrode 10 is longer than a
column-directional length of protrusion 21 formed at sustain
electrode 20. Address discharges occur between address electrodes
110 and scan electrodes 10 in the address interval. In the first
exemplary embodiment, an area where address and scan electrodes 110
and 10 face each other increases to stably generate an address
discharge. As shown in FIG. 1, substantially 2/3 of the total light
emission is generated at the cathode in the sustain interval.
Therefore, when a voltage applied to scan electrode 10 is less than
a voltage applied to sustain electrode 20 in the sustain interval,
that is, when scan electrode 10 operates as a cathode with respect
to sustain electrode 20, light emission is more effectively
performed because the length of protrusion 11 of scan electrode 10
is long.
[0031] The column-directional length of protrusion 11 of scan
electrode 10 is increased in the exemplary embodiment, and further,
a width of protrusion 11 can be greater than that of protrusion 22
of sustain electrode 20, and an area of protrusion 11 can be
greater than that of protrusion 21.
[0032] In addition, when scan electrode 10 operates as a cathode, a
sustain pulse, such as that depicted in FIG. 4, can be applied to
scan electrodes 10 and sustain electrodes 20 so as to maintain a
sufficient discharge time.
[0033] Referring still to FIG. 4, a PDP apparatus drive method
according to the first exemplary embodiment of the present
invention will now be described. In the first embodiment, it is
assumed that a sustain pulse alternately having voltages Vs/2 and
-Vs/2 is applied to scan electrodes 10 and sustain electrodes 10 20
so that a potential difference of two electrodes 10 and 20 may be
voltage Vs in the sustain interval, voltage Vs being a voltage for
allowing the generation of a sustain discharge. It is also possible
to apply another type of a pulse that causes the potential
difference of two electrodes 10 and 20 to be voltage Vs, which will
be applicable to the first through fourth exemplary
embodiments.
[0034] FIG. 4 shows a PDP apparatus drive waveform according to the
first exemplary embodiment of the present invention. Negative
voltage Vy2 is applied to scan electrode 10 and positive voltage
Vx1 is applied to sustain electrode 20 in interval T1 of a single
sustain pulse in the sustain interval. Since scan electrode 10 with
a long protrusion compared to that of sustain electrode 20 in
interval T1 operates as a cathode, a discharge diffusion time at
protrusion 11 of scan electrode 10 increases to increase the
luminance. In this instance, interval T1 for applying a negative
voltage to scan electrode 10 is lengthened so as to maintain
voltages Vy2 and Vx1 applied to scan electrodes 10 and sustain
electrodes 20 while maintaining the discharge. Interval T2 for
applying negative voltage Vx2 to sustain electrode 20 is reduced by
the increment of interval T1 so as to maintain a total number of
sustain pulses in the sustain interval.
[0035] In the first embodiment, the length of protrusion 11 of scan
electrode 10 is established to be longer than that of protrusion 21
of sustain electrode 20, and the interval for applying a negative
voltage to scan electrode 10 is set to be longer than that for
applying a negative voltage to sustain electrode 20. As a result,
the area of protrusion 11 of scan electrode 10 becomes greater to
improve address discharge efficiency during the address interval,
and an interval for applying a negative voltage to scan electrode
10 increases to increase the luminance.
[0036] However, since the length of protrusion 21 is short in
interval T2 during which sustain electrode 20 operates as a
cathode, the discharge diffusion time shortens, and hence, the
luminance can be reduced in interval T2. With reference to FIGS. 5
through 7, methods for compensating for the luminance in interval
T2 during which sustain electrode 20 operates as a cathode will now
be described.
[0037] FIGS. 5 through 7 show PDP drive waveforms according to
second through fourth exemplary embodiments of the present
invention.
[0038] Referring to FIG. 5, levels of negative voltages Vx2 and Vy2
are lowered in the sustain pulse according to the second embodiment
compared to the sustain pulse of FIG. 4. That is, intensities of
negative voltages Vx2 and Vy2 are made greater than those of
positive voltages Vx1 and Vy1, and are applied to sustain and scan
electrodes 20 and 10. Accordingly, when negative voltage Vx2 is
applied to sustain electrode 20 in interval T2, a potential
difference between sustain electrode 20 and scan electrode 10 and a
potential difference between address electrode 110 and sustain
electrode 20 are increased to improve the luminance. That is, when
sustain electrode 20 operates as a cathode in interval T2,
shortened protrusion 21 of sustain electrode 20 can be compensated
by increasing the potential difference between scan electrode 10
and sustain electrode 20, and since the intensity of negative
voltage Vy1 of scan electrode 10 is also increased, the luminance
is further improved when scan electrode 10 operates as a
cathode.
[0039] The intensity of the negative voltage applied to scan
electrode 10 is increased in the second embodiment, and differing
from this, a pulse (i.e., a pulse shown as a dotted line in FIG. 5)
corresponding to the existing sustain pulse can be applied to scan
electrode 10.
[0040] In the sustain pulse according to the third embodiment,
referring to FIG. 6, levels of negative voltages Vx2 and Vy2 of the
sustain pulse of FIG. 4 are lowered in the like manner of the
second embodiment. Interval T1 for applying a negative voltage to
scan electrode 10 is lengthened, and interval T2 for applying a
negative voltage to sustain electrode 20 is shortened. As a result,
the discharge diffusion time is lengthened by the length of
protrusion 11 of scan electrode 10 in interval T1 during which scan
electrode 10 is a cathode to thereby increase the luminance, and
since interval T1 is long, the applied voltage is maintained during
the discharge diffusion time. In interval T2 during which sustain
electrode 20 is a cathode, since negative voltage Vx2 applied to
sustain electrode 20 has been greatly increased, the potential
difference between sustain electrode 20 and scan electrode 10 and
the potential difference between sustain electrode 20 and address
electrode 110 increase to activate the discharge and improve the
luminance.
[0041] Referring to FIG. 7, in the sustain pulse according to the
fourth embodiment, the negative voltage applied to scan electrode
10 corresponds to the existing sustain pulse, differing from the
third embodiment. That is, a time for applying negative voltage Vy2
is increased to maintain the discharge when scan electrode 10
becomes a cathode, and negative voltage Vx2 is increased to
compensate for the luminance reduction when sustain electrode 20
becomes a cathode.
[0042] According to the present invention, an address discharge can
be effectively generated because of the large size of the
protrusion of the scan electrode. The discharge is maintained for a
long time since the time for applying a negative voltage to the
scan electrode is long. Also, the size of the protrusion of the
sustain electrode is decreased to compensate for the reduced
luminance since the negative voltage applied to the sustain
electrode is large.
[0043] While this invention has been described in connection with
what is presently considered to be practical embodiments, it is to
be understood that the invention is not limited to the disclosed
embodiments, but, on the contrary, is intended to cover various
modifications and equivalent arrangements included within the
spirit and scope of the appended claims.
* * * * *